Task 4 of the AI order assistant plan.
Pure core, no I/O:
- PLACEHOLDER_LINE_PATTERNS, isRealOrderLine
- orderLinesHash (sha1 over sorted id|description|quantity)
- isOrderEligible (no quote, >=1 real pending line, not already matched
on the same lines unless forced, not in the AI-error cooldown)
- decideOutcome — the auto-link rule: high confidence, every real line
paired "sure" on the chosen quote, same company, auto-link on
- confidenceToScore (0.9 / 0.7 / 0.5)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
